<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>selectionFullyContained 需手动精准选中元素</title>
</head>
<body>
  <canvas id="canvasBox" width="600" height="600" style="border: 1px solid #ccc;"></canvas>

  <script src="../../script/fabric.js"></script>
  <script>
  
    let canvas = new fabric.Canvas('canvasBox', {
      selectionFullyContained: true // 当设置为 true 时，只有真实选中元素才有选框出现
    })
  
    // 三角形
    const triangle = new fabric.Triangle({
      top: 100,
      left: 50,
      width: 80, // 底边宽度
      height: 100, // 底边到定点的距离
      fill: 'blue',
    })

    canvas.add(triangle)
  
  </script>
</body>
</html>